Question

1. How many electrons appear in the Lewis symbol for an element whose electron configuration is 1s'2s'2p? a. 2 b. d. 2. In which of the following ionic compounds are ions with a +2 charge present? a LiSe c Mg,Si d. SnO 3. The Roman numeral ." in the name iron(m) oxide indicates that: a. iron is present in the form of +3 ions b. there are three iron atoms per formula unit c. there are three oxygen atoms per formula unit. d. there are three times as many iron atoms present as oxygen atoms. 4. In which of the following pairings is the chemical formula not consistent with the ions shown? М., Х", МХ, d. no correct response 5. Which of the following compounds contain more than 10 atoms per formula unit? a. ammonium chloride b. barium carbonate c.iron(il) cyanide d. aluminum sulfate 6. Characterize EACH of the three given statements as being TRUE or FALSE and then indicate the collective true-false status of the statements using the choices The number of valence electrons possessed by an atom can never exceed four The symbol for an atom of X that has lost two electrons is X . .In all ionic compounds the total charge of the ions present per formula unit must add up to zero a. All three statements are true. c. Only one of the statements is true.d. None of the statements are true. 7. For the electron configuration 15'25 2p 3s'3p 4s'3d 4p', choose the appropriate number of valence electrons b. Two of the three statements are true. present from the response list a. 5 valence electrons 8. Choose a formula from the response list with -2 charged monoatomic ions present. a. LiN 9. Choose a formula from the response list where two ions are present per formula unit. a. K N 10. Choose the polyatomic ion that has a negative two charge a. sulfite ion b. c 15 valence electronsd. 13 valence electrons 3 valence electrons b. Caf c. Mgo d. (NH4)SO b. AIF d. CaSO b. hydroxide ion C sulfide ion d. ammonium ion

Answer 1

1s^2 2s^2 2p^2 outer shell electrons option (b) 4 is the answer Option (c) is the answer charge of Mg is 2 + which is the subscript of Si In Li-2 Se Li is + 1 Se is -2 Al_2 Te_3 Al is + 3 Te is -2 SnO_2 S_n is 4 + O is -2 Iron (III) oxide is Fe_2 O_3 formed by criss crossing charge numbers So, option (a) is the answer Option (b) is not consistent with the formula shown M)2 x_1 rightarrow M_3 x should be the formula instead of Mx_3 given (a) NH_4 Cl = 6 atoms (b) BaCO_3 = 5, atoms (c) Fe (CN)_3 = 7, atoms (d) Al_2 (SO_4)_3 = 17, atoms option (d) is the answer Statement (1) is false valence electrons can be till (8) Statement (2) is false = > lost 2e^- will be x^2 + statement (3) is True So option (c) is the Answer. 3 valence electrons option (b) is the Answer.